The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/depot_tools/+/d64781e17af7bc40cf5a3ac9321c48907a02c219

commit d64781e17af7bc40cf5a3ac9321c48907a02c219
Author: Edward Lemur <ehmaldonado@chromium.org>
Date: Wed Jul 11 23:09:55 2018

gclient_scm: Fetch refs/changes/* when syncing.

When a git mirror is configured, it fetches only refs/heads/*,
and possibly branch-heads and tags, but not refs/changes.

When gclient attempts to sync refs/changes/* from a mirror,
it fails, since the mirror has no such objects.

See for example [1], where the DEPS entry for builtools was
modified to sync to a CL, but all the bots failed to sync to it.

This change modifies gclient to always fetch refs/changes/*
directly from the repo, even when a mirror is configured.

[1] https://chromium-review.googlesource.com/c/chromium/src/+/1119098/6

Bug: 858894

Change-Id: I71bb313e4325a81b2985db1d00c70a8844dc7c22
Reviewed-on: https://chromium-review.googlesource.com/1119525
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Aaron Gable <agable@chromium.org>

[modify] https://crrev.com/d64781e17af7bc40cf5a3ac9321c48907a02c219/testing_support/fake_repos.py
[modify] https://crrev.com/d64781e17af7bc40cf5a3ac9321c48907a02c219/tests/gclient_scm_test.py
[modify] https://crrev.com/d64781e17af7bc40cf5a3ac9321c48907a02c219/gclient_scm.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3789a4a02293b9ded7d922cfc47462e25d7bc20d

commit 3789a4a02293b9ded7d922cfc47462e25d7bc20d
Author: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Date: Thu Jul 12 00:29:12 2018

Roll src/third_party/depot_tools c3975e55e146..d64781e17af7 (1 commits)

https://chromium.googlesource.com/chromium/tools/depot_tools.git/+log/c3975e55e146..d64781e17af7


git log c3975e55e146..d64781e17af7 --date=short --no-merges --format='%ad %ae %s'
2018-07-11 ehmaldonado@chromium.org gclient_scm: Fetch refs/changes/* when syncing.


Created with:
  gclient setdep -r src/third_party/depot_tools@d64781e17af7

The AutoRoll server is located here: https://depot-tools-chromium-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.



BUG=chromium:858894
TBR=agable@chromium.org

Change-Id: If022f0d17cbb6ad978d73fb45f85215dfca5033e
Reviewed-on: https://chromium-review.googlesource.com/1134447
Reviewed-by: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#574428}
[modify] https://crrev.com/3789a4a02293b9ded7d922cfc47462e25d7bc20d/DEPS